In the first class of explanations the explosion itself is the delayed neutrino mechanism. It seems that the heavily studied delayed neutrino mechanism ([1]}, [2]}, [3]}, [4]}, [5]}, [6]}, [7]}, [8]}, [9]}, [10]}, [11]}, [12]}; for a recent brief optimistic review of this mechanism see [13]}) cannot reach CCSN explosion energies of \(E_{\rm SN} 2 \times 10^{51} {~\rm erg}\)  (e.g., [14]}, [15]}, [16]}, [17]}, [18]}, [19]}). Many studies of SLSNe and LSNe that take the explosion itself to be by the delayed neutrino mechanism attribute the extra energy of LSNe and SLSNe to a magnetar, i.e., a rapidly rotating magnetized neutron star (e.g., [20]}, [21]}, [22]}, [23]}, [24]}).
